Merge pull request #5926 from mdboom/new-dash-styles

Fix #5917. New dash patterns. Scale dashes by lw

lib/matplotlib/backend_bases.py

@@ -55,6 +55,7 @@
 from matplotlib import is_interactive
 from matplotlib import get_backend
 from matplotlib._pylab_helpers import Gcf
+from matplotlib import lines
 
 from matplotlib.transforms import Bbox, TransformedBbox, Affine2D
 
@@ -771,14 +772,6 @@ class GraphicsContextBase(object):
     An abstract base class that provides color, line styles, etc...
     """
 
-    # a mapping from dash styles to suggested offset, dash pairs
-    dashd = {
-        'solid': (None, None),
-        'dashed': (0, (6.0, 6.0)),
-        'dashdot': (0, (3.0, 5.0, 1.0, 5.0)),
-        'dotted': (0, (1.0, 3.0)),
-    }
-
     def __init__(self):
         self._alpha = 1.0
         self._forced_alpha = False  # if True, _alpha overrides A from RGBA
@@ -870,7 +863,16 @@ def get_dashes(self):
 
         Default value is None
         """
-        return self._dashes
+        if rcParams['_internal.classic_mode']:
+            return self._dashes
+        else:
+            scale = max(1.0, self.get_linewidth())
+            offset, dashes = self._dashes
+            if offset is not None:
+                offset = offset * scale
+            if dashes is not None:
+                dashes = [x * scale for x in dashes]
+            return offset, dashes
 
     def get_forced_alpha(self):
         """
@@ -1047,21 +1049,12 @@ def set_linewidth(self, w):
     def set_linestyle(self, style):
         """
         Set the linestyle to be one of ('solid', 'dashed', 'dashdot',
-        'dotted'). One may specify customized dash styles by providing
-        a tuple of (offset, dash pairs). For example, the predefiend
-        linestyles have following values.:
-
-         'dashed'  : (0, (6.0, 6.0)),
-         'dashdot' : (0, (3.0, 5.0, 1.0, 5.0)),
-         'dotted'  : (0, (1.0, 3.0)),
+        'dotted'). These are defined in the rcParams
+        `lines.dashed_pattern`, `lines.dashdot_pattern` and
+        `lines.dotted_pattern`.  One may also specify customized dash
+        styles by providing a tuple of (offset, dash pairs).
         """
-
-        if style in self.dashd:
-            offset, dashes = self.dashd[style]
-        elif isinstance(style, tuple):
-            offset, dashes = style
-        else:
-            raise ValueError('Unrecognized linestyle: %s' % str(style))
+        offset, dashes = lines.get_dash_pattern(style)
 
         self._linestyle = style
         self.set_dashes(offset, dashes)

lib/matplotlib/collections.py

@@ -28,6 +28,7 @@
 import matplotlib.path as mpath
 from matplotlib import _path
 import matplotlib.mlab as mlab
+import matplotlib.lines as mlines
 
 
 CIRCLE_AREA_FACTOR = 1.0 / np.sqrt(np.pi)
@@ -531,23 +532,16 @@ def set_linestyle(self, ls):
             The line style.
         """
         try:
-            dashd = backend_bases.GraphicsContextBase.dashd
             if cbook.is_string_like(ls):
                 ls = cbook.ls_mapper.get(ls, ls)
-                if ls in dashd:
-                    dashes = [dashd[ls]]
-                else:
-                    raise ValueError()
+                dashes = [mlines.get_dash_pattern(ls)]
             elif cbook.iterable(ls):
                 try:
                     dashes = []
                     for x in ls:
                         if cbook.is_string_like(x):
                             x = cbook.ls_mapper.get(x, x)
-                            if x in dashd:
-                                dashes.append(dashd[x])
-                            else:
-                                raise ValueError()
+                            dashes.append(mlines.get_dash_pattern(x))
                         elif cbook.iterable(x) and len(x) == 2:
                             dashes.append(x)
                         else:

lib/matplotlib/lines.py

@@ -37,6 +37,24 @@
 from matplotlib import _path
 
 
+def get_dash_pattern(style):
+    """
+    Given a dash pattern name from 'solid', 'dashed', 'dashdot' or
+    'dotted', returns the (offset, dashes) pattern.
+    """
+    if style == 'solid':
+        offset, dashes = None, None
+    elif style in ['dashed', 'dashdot', 'dotted']:
+        offset = 0
+        dashes = tuple(rcParams['lines.{}_pattern'.format(style)])
+    elif isinstance(style, tuple):
+        offset, dashes = style
+    else:
+        raise ValueError('Unrecognized linestyle: %s' % str(style))
+
+    return offset, dashes
+
+
 def segment_hits(cx, cy, x, y, radius):
     """
     Determine if any line segments are within radius of a

lib/matplotlib/mpl-data/stylelib/classic.mplstyle

@@ -15,6 +15,9 @@ lines.dash_capstyle : butt          # butt|round|projecting
 lines.solid_joinstyle : round       # miter|round|bevel
 lines.solid_capstyle : projecting   # butt|round|projecting
 lines.antialiased : True         # render lines in antialiased (no jaggies)
+lines.dashed_pattern : 6, 6
+lines.dashdot_pattern : 3, 5, 1, 5
+lines.dotted_pattern : 1, 3
 
 ### Marker props
 markers.fillstyle: full

lib/matplotlib/rcsetup.py

@@ -275,18 +275,18 @@ def validate_maskedarray(v):
 
 
 class validate_nseq_float(object):
-    def __init__(self, n):
+    def __init__(self, n=None):
         self.n = n
 
     def __call__(self, s):
         """return a seq of n floats or raise"""
         if isinstance(s, six.string_types):
-            s = s.split(',')
+            s = [x.strip() for x in s.split(',')]
             err_msg = _str_err_msg
         else:
             err_msg = _seq_err_msg
 
-        if len(s) != self.n:
+        if self.n is not None and len(s) != self.n:
             raise ValueError(err_msg.format(n=self.n, num=len(s), s=s))
 
         try:
@@ -296,18 +296,18 @@ def __call__(self, s):
 
 
 class validate_nseq_int(object):
-    def __init__(self, n):
+    def __init__(self, n=None):
         self.n = n
 
     def __call__(self, s):
         """return a seq of n ints or raise"""
         if isinstance(s, six.string_types):
-            s = s.split(',')
+            s = [x.strip() for x in s.split(',')]
             err_msg = _str_err_msg
         else:
             err_msg = _seq_err_msg
 
-        if len(s) != self.n:
+        if self.n is not None and len(s) != self.n:
             raise ValueError(err_msg.format(n=self.n, num=len(s), s=s))
 
         try:
@@ -836,6 +836,9 @@ def validate_hist_bins(s):
     'lines.solid_joinstyle': ['round', validate_joinstyle],
     'lines.dash_capstyle':   ['butt', validate_capstyle],
     'lines.solid_capstyle':  ['projecting', validate_capstyle],
+    'lines.dashed_pattern':  [[2.8, 1.2], validate_nseq_float()],
+    'lines.dashdot_pattern': [[4.8, 1.2, 0.8, 1.2], validate_nseq_float()],
+    'lines.dotted_pattern':  [[1.2, 0.6], validate_nseq_float()],
 
     # marker props
     'markers.fillstyle': ['full', validate_fillstyle],

matplotlibrc.template

@@ -90,6 +90,11 @@ backend      : $TEMPLATE_BACKEND
 #lines.solid_capstyle : projecting   # butt|round|projecting
 #lines.antialiased : True         # render lines in antialiased (no jaggies)
 
+# The three standard dash patterns.  These are scaled by the linewidth.
+#lines.dashed_pattern : 2.8, 1.2
+#lines.dashdot_pattern : 4.8, 1.2, 0.8, 1.2
+#lines.dotted_pattern : 1.2, 0.6
+
 #markers.fillstyle: full # full|left|right|bottom|top|none
 
 ### PATCHES

src/py_converters.cpp

@@ -476,7 +476,7 @@ int convert_gcagg(PyObject *pygc, void *gcp)
           convert_from_attr(pygc, "_antialiased", &convert_bool, &gc->isaa) &&
           convert_from_attr(pygc, "_capstyle", &convert_cap, &gc->cap) &&
           convert_from_attr(pygc, "_joinstyle", &convert_join, &gc->join) &&
-          convert_from_attr(pygc, "_dashes", &convert_dashes, &gc->dashes) &&
+          convert_from_method(pygc, "get_dashes", &convert_dashes, &gc->dashes) &&
           convert_from_attr(pygc, "_cliprect", &convert_rect, &gc->cliprect) &&
           convert_from_method(pygc, "get_clip_path", &convert_clippath, &gc->clippath) &&
           convert_from_method(pygc, "get_snap", &convert_snap, &gc->snap_mode) &&